The present invention relates to a process for conditioning solid radioactive waste having large dimensions, constituted by contaminated objects such as cartridge filters, metal chips, tools, etc. Generally the activity of such solid radioactive waste does not exceed 10 Ci/m.sup.3.
Hitherto the conditioning of large radioactive waste, such as that defined hereinbefore, has taken place by encasing in concrete blocks. Encasing in concrete has been carried out either by introducing the waste into concrete vessels which were then sealed by a concrete plug, or by introducing the waste into moulds in which the concrete was then cast. This conditioning process using concrete ensures a good biological protection against ionising radiation from the thus confined waste, but due to the fact that concrete has a poor long term behaviour and a limited resistance to weather and leaching, the concrete blocks encasing the radioactive waste do not have a perfect sealing.
French Pat. No. 2,129,836 filed on Mar. 16th, 1971 by the present Applicant relates to a process for conditioning radioactive waste reduced to the form of a dry powder according to which the pulverulent radioactive waste is incorporated into a resin which is polymerisable at ambient temperature and then said resin is polymerised.
In said process the resin polymerisable at ambient temperature in particular comprises a polyester resin such as a glycol-maleophthalate-based resin mixed with styrene. Although the process described in French Pat. No. 2,129,836 has proved satisfactory in the case of pulverulent radioactive waste, it cannot be used for solids with large dimensions.